Finally, GENyUS has made the new CFW!They fixed the Bugs GEN-C had.Here is some More Info:

(by dl.qj.net)* All features of 5.50GEN-B2 are available* Ability to run 5.51 + games without having to patch it (UMD or ISO)* Possibility to launch PSN demos requiring 5.51 + without having to patch them (as MGS for example)* Possibility to connect to the Playstation Store by the using of MEDIAGO, to retrieve games and goodies without having to install Fake USB or other complicated stuff.* Possibility to use the XGEN Updater to install the official firmware 6.10 (use it only if you have a Pandora XGEN to be able to return later in Custom firmware)* 480x272 AVC Videos ere supported

An option to accelerate reading of the memory stick (the fatmsmod, I presume) is also in the process of getting ported to the 5.50GEN releases.